Many studies (e.g. [1]}, [2]}, [3]}) attempt to relate forced (annual) oscillations to polar motion RP (\(m_1\) , \(m_2\) ) or length of day (lod) (data file EOPC01IAU2000, [4]}, maintained by IERShttps://www.iers.org/IERS/EN/DataProducts/EarthOrientationData/eop.html). The data are shown and discussed in [5]}. The annual SSA components of \(m_1\)  and \(m_2\)  are displayed in Figure REF . Both undergo some amount of modulation. That modulation is significant for \(m_1\) , particularly between 1850 and 1930. For \(m_2\) , it is smaller and more regular. A \(m_1\)  vs \(m_2\)  diagram (see Appendix A) shows the classical Lissajou elliptical shape of annual polar motion. Note that the date of 1930 is when the Chandler wobble undergoes a phase jump of \(\pi \)  (e.g. [6]}, [7]}). The lod data start only in 1962 (not shown, see [8]}). The annual and semi-annual SSA components of lod are modulated (Figure REF  and Figure REF ). The annual component grows slightly until 1990, flattens until 2013 and then starts growing again. The semi-annual component decreases regularly over the sixty years of available data.
<FIGURE><FIGURE>